Clutch mechanism for motor cars



p 1933- o. SIEIDENBERG 2,130,907

CLUTCH MECHANISM FOR MOTOR CARS Filed April 28, 19:50

ATTORN EYS Patented Sept. 20, 1938 PATENT OFFICE CLUTCH lVIECHANISM FORMOTOR CARS Otto Seidenberg, Berlin, Germany, assignor, by

mesne assignments, to Bendix Aviation Corporation, Chicago, 111., acorporation of Delaware Application April 28,

1930, Serial No. 448,028

In Germany May 1, 1929 7 Claims.

V This invention is concerned with a clutch mechanism'for motor drivenvehicles in which the gas pedal or accelerator isexclusively used forthrowing the clutch into and out of action.

In devices of this kind it is of particular importance that all themovements of the pedal are transmitted on the throttle valve of 'thecarburettor and the control valve for the vacuum cylinder for the clutchmotion with a certain play and as softly as possible in order that heavyshocks are avoided upon the clutch being thrown in or out of action.According to this present invention I obtain this result by arrangingthe known'lost motion between the control valve and the gas pedal withinthe valve itself without increase of its stroke whereas simultaneouslythe 7 outlet for the air from the operating cylinder for the clutch canbe controlled by a brake valve controlled by the operating piston in itsone end 20 position. I

In order that myinvention may be readily understood by those skilled inthe art reference may be had to the drawing illustrating apreferredembodiment of my invention, and in which Fig; 1 is adiagrammatic illustration of my complete clutch operating system,

' Fig. 2 a section of the operating cylinder for the clutch movement,and the retarding or throttling valve associated with the said cylinder,

Fig. 3 a section of the reversing valve.

' The clutch mechanism comprises a reversing valve i and operatingcylinder} having a retarding or throttling valve 3 and a controllednozzle 4. 'A cut-off cock 5 permits the operator to put the whole systemout of operation.

Within the reversing valve I I arrange a valve member lt which isconnected by a linkage 8 with the gas pedal 1 being under the influenceof a tension spring 6. The casing of valve l is connected with themanifold 53 of the machine driving combustion engine and with the clutchactuating cylinder 2 by conduits l5, 16, the valve member 18 governingthe movements of a piston I1 reciprocating within the cylinder 2 as willbe explained more in detail hereinafter.

The carburettor ID carries the throttle valve actuating lever l2 whichis under the influence of a tension spring H and which is connected by alinkage l3 with the gas pedal .1, the said linkage being provided with aplay or lost motion M, permitting thepedal l to rock a certain angulardistance, beforeany action on the throttle valve is produced. Thelinkage 8 acts on the valvemember ill of the valve lnwhich is con- 552structedand. actingas 'athree-waywalve so that,

either the conduits l5, l6 from the manifold 9 to the operating cylinder2 are open and the air passage l9 leading from the interior of the valvecasing to the outer atmosphere is closed, or that this latter passage isopen and the communication of the cylinder 2 with the manifold 9 isinterrupted. The valve I thus may in fact permit, under certainoperating conditions, an inflow of fresh air into the manifold 9 duringthe movement of the valve member l8. However, since the stroke of thismember is very small and usually does not exceed 3 mm., and since thisstroke is performed very quickly, the volume of the fresh air thussupplied to the manifold 9 is so small that it is of no significance forthe operation of the motor.

It is Well known that with clutch mechanisms of the character described,a certain amount of play or lost motion is introduced between the pedal1 and the valve member l8 in order that the further movement of the gaspedal after clutch engagement may take place without obstruction orhindrance. As far as I know this play or lost motion has, with formerlyused devices, been interposed into the operating linkage outside thevalve casing by the controlling cone or valve member l8 being extendedoutside the casing by means of a rigidly acting pin or rod within which,that is outside the valve casing, the play or lost motion was arranged.This known device was objectionable in that the controlling cone orvalve member was put under tilting strains so that it could not beuniformly pressed upon its point or cone in an exactly axial direction,so that frequently leakages were produced which are very objectionableview of the comparatively small vacuum.

In accordance with this present invention I avoid this objection byconstructing the valve as illustrated in Fig. 3. Accordingly the conicalvalve member I8 is separately guided within the valve casing l whereasthe rod 8 actuating the valve member has no rigid connection therewithbut may freely slide within the central bore or recess 3| of member 18,the rod 8 having at its one end merely an enlarged head 32 by which thevalve member 18 may be slid against the action 01 a spring 33 so as toestablish communication of the conduits l5 and I6. It will be readilyappreciated that by this construction an exactly axial motion of thevalve member may be obtained so that the same may always be in an exactand tight contact with its valve seat.

Within the cylinder 2 I arrange an operating piston H which acts on. thevehicle clutch so as.

to throw the same into or out of operation, Fig. 2 illustrating theoperating system in the position of the parts which they assume when theclutch is thrown out. The piston I1 is, by means of the piston rod 23,connected with the clutch operating lever 2|, the latter being under theinfluence of a suitable clutch spring 22 tending to throw the clutchinto action and to move piston I1 towards the left hand end of itscylinder 2 (Fig. 2). The piston may also be acted upon by the vacuumexisting within the manifold 93, this vacuum communicating with the rearend of the cylinder 2 by the conduits I5 and I6 when the control valve II is correspondingly adjusted. It will be understood that whenever thevacuum within the manifold '9 is communicated to the cylinder 2 thepiston I1 is retracted into its clutch opening position contrary to theaction of the clutch spring 22. a

The vacuum might be very abruptly destroyed in the rear end compartmentof piston I 'I by the operation of the control valve I resulting in theclutch being thrown in with a shock or snap action. According to afurther feature of my invention there is provided a brake mechanismbraking the piston I! in its clutch engaging movement so that the clutchmay be shifted into operation in a soft manner. This retardation orbraking of the movement of piston I! is obtained by the retarding orthrottling valves 3 and 4 carried by the operating cylinder 2 and dashrespectively the valve 3 being acted upon immediately before the clutchis engaged by an adjustable driver 24 carried by the piston rod 23 andco-operating with a disc 26 on the valve spindle 25. When the piston rod23 is projected by clutch spring 22 after the vacuum conduits I5, I6 areinterrupted by valve I, the driver 24 pulls the valve rod 25 forwardly,compressing a spring 2?, so that the spring 28 of the valve disc 29 mayoperate the retarding valve 3 and close the air exit passage 29'indicated in Fig. 2 by an arrow, so that the air contained within thecylinder may only be discharged through a conduit 3!] being under themanual control of valve 4 on the dash of the vehicle. When the piston I!is retracted it permits a return of the valve rod 25 under the action ofthe spring 21 lifting the valve disc 29 from its seat against the actionof spring 28 so that the retarding valve is again opened and the pistonII is immediately retracted into its clutchdisengaged position. In Fig.2 the plain lines illustrate the clutch disengaged and the dotted linesthe clutch engaged position of the piston rod 23. The'control nozzle 4connected with the operating cylinder by tube 30 serves to permit acontrolled egress of air from the cylinder and thus effect passage andthus a soft and resilient clutch engaging action of the clutch which maybe perfectly accommodated to the character of the respective clutchconstruction.

The operation of the reversing valve I requires. that a lost motion M bearranged in the linkage I3 in order that the valve I may at first beoperated without influencing however the position of the throttle valveI 2.

v The operation of the new clutch system is as follows: i

In the diagram Fig. 1 the gas pedal is assuming its position I at whichthe motor is running idle and the clutch has not yet been thrown intoaction. The reversing valve I is closing the air passage I9 and isestablishing communication between the manifold 9 and the clutchoperating cylinder 2 so that the vacuum existing within the manifold 9when the machine is running will now act on the cylinder 2 and retractthepiston l1 into its clutch disengaged position tensioning the clutchspring 22. The clutch is thus thrown out and the motor running idle. 7

If now the gas pedal or accelerator I is rocked into the position IIthere results an operation of the valve I8 and the position of thethrottle valve I2 of the carburettor I0 is in no way changed, on

account of the lost motion I4 interposed into the linkage I3. The motoris thus still running idle; the reversing valve I has now howeverinterrupted the vacuum conduit to the manifold 9 and establishedcommunication with the outer atmosphere, that is established acommunication between the valve passage I9 and the passage I5 leading tothe rear end at the cylinder. Accordingly air of atmospheric pressurethen flows into the compartment behind the piston I1 so that the vacuumis destroyed and the clutch spring 22 permitted to rock theclutch lever-2I into its clutch engaged position. Since at this stage of theoperation the retarding or braking valve 3 is still opened this movementof piston-l1 is at first performed rather quickly, the movement beinghowever retarded or braked immediately before the clutch is thrown in,since the driver 2 of the piston rod 23 closes the valve 3 as aboveexplained. The air which is still within the cylinder 2 will thus becompressed by the piston I1 so as to retard the movement thereof, theair being permitted to escape at a slower or quicker rate depending uponthe adjustment of the control cook or nozzle 4. Accordingly the clutchis, as a result of this air cushioning effect, thrown softly andresiliently into action,

If the gas pedal 1 is in its position III, the reversing valve I isstill in the same adjustment as before. The pressure conditions withinthe operating cylinder remain the same. The clutch remains engaged andthe motor is now running with full speed or power since the gas lever 'Ihas now fully opened the throttle valve I2 of the carburettor, the fuelinlet to the carburettor thus being controllable within the rangebetween the positions II and III.

The braking of the motor is effected in the following way:

If the gas pedal 1 is in its position II, the motor is running idle andthe clutch engaged, as above 0 described. In this condition the motormay act as a brake as will be readily understood by those familiar withthis art.

As is obvious from the above specification the clutch mechanism may bedescribed as a selfcontained independent unity. The same can thus bemounted upon an automobile of any type and size, the simplicity ofthe'whole system permitting the use of standard parts for constructingit and even permitting the motorcar driver of average skill to himselfinstall the above described clutch operating system on his vehicle.

I claim: a

1. In a motor vehicle, the combination, with the engine and itsmanifold, the accelerator, and the clutch mechanism, of a cylinderclosed at both ends having a piston reciprocating therein, an operativeconnection between said piston and the clutch mechanism, a fluidtransmitting connection between said cylinder at one side of thepistonand said manifold, means controlled by said accelerator foropening and closing said fluid transmitting connection, the chamber ofthe cylinder located at the side of the piston opposite. to the partcommunicating with said manifold communicating with the outer air, anormally open valve adapted partly to close said chamber, and meanscontrolled by said piston operative near the end of the clutch closingstroke thereof for moving said valve into position for partly closingsaid chamber and adapted upon the return stroke of said piston to movethe valve into opening position.

2. In a motor vehicle, the combination, with the engine and itsmanifold, the accelerator, and the clutch mechanism, of a cylinderclosed at both ends having a piston reciprocating therein, an operativeconnection between said piston and the clutch mechanism, a fluidtransmitting connection between said cylinder at one side of the pistonand said manifold, means controlled by said accelerator for opening andclosing said fluid transmitting connection, the chamber of the cylinderlocated at the side of the piston opposite to the part communicatingwith said manifold being open to the outer air, a normally open valveadapted partly to close said chamber, a spring tending to move saidvalve into position for opening said chamber to the outer air, and meansconnected with said piston and adapted near the end of the clutchclosing stroke of the piston to relieve said valve of the pressure ofsaid spring and to allow the same to move into position for partlyclosing said chamber to the outer air.

3. In a motor vehicle, the combination, with the engine and itsmanifold, the accelerator, and the clutch mechanism, of a cylinderclosed at both ends having a piston reciprocating therein, an operativeconnection between said piston and the clutch mechanism, a fluidtransmitting connection between said cylinder at one side of the pistonand said manifold, the chamber of said cylinder located at the side ofthe piston opposite to the part communicating with said manifold beingprovided with an opening and a vent, a valve adapted to close saidopening, and means controlled by said piston and operative near the endof the clutch closing stroke thereof for moving said valve into positionfor closing said opening and other means adapted upon the return strokeof said piston to return the valve intoopening position.

4. In a motor vehicle, the combination, with the engine and itsmanifold, the accelerator, and the clutch mechanism, of a cylinderclosed at both ends having a piston reciprocating therein, an operativeconnection between said piston and the clutch mechanism, a fluidtransmitting connection between said cylinder at one side of the pistonand said manifold, the chamber of said cylinder located at the side ofthe piston opposite to the part communicating with said manifold beingprovided with an opening and a vent, a

valve adapted to close said opening, means controlled by said piston andoperative near the end of the clutch closing stroke for moving saidvalve into position for closing said opening and other means adapted toreturn the same into opening position upon the return stroke of saidpiston, and means for regulating said vent.

5. In a motor vehicle, the combination, with the engine and itsmanifold, the accelerator, and the clutch mechanism, of a cylinderclosed at both ends having a piston reciprocating therein, an operativeconnection between said piston and the clutch mechanism, a fluidtransmitting connection between said cylinder at one side of the pistonand said manifold, the chamber of said cylinder located at the side ofthe piston opposite to the part communicating with said manifold beingopen to the outer air, a valve adapted partly to close said chamber tothe outer air, springs acting on said valve one tending to move the sameinto opening position and the other tending to move the same intoclosing position, and a stern acting on said spring tending to hold thevalve in opening position and adapted to be engaged by said pistonmoving into clutch applying position near the end of the clutch closingstroke thereof for rendering said spring tending to open the valveinoperative.

6. In a motor vehicle, the combination, with the engine and itsmanifold, the accelerator, and the clutch mechanism, of a cylinderhaving a piston reciprocating therein, an operative connection betweensaid piston and the clutch mechanism, a fluid transmitting connectionbetween said cylinder and said manifold, and a valve controlled by saidaccelerator for opening and closing said fluid transmitting connection,said valve comprising a casing included in said fluid transmittingconnection, a valve body slidable in said casing, a spring acting onsaid valve body in a direction for closing said fluid transmittingconnection, and a stem connected with said accelerator and movablerelatively to said valve body in the direction of the action of saidspring and adapted for positive engagement therewith when moving in theother direction.

7. In apparatus of the class described, a cylinder having cover platesat its ends, a piston in said cylinder, means for connecting one end ofsaid cylinder to a source of lower than atmospheric pressure, arelatively large opening at the other end of the cylinder, a valveadapted to be operated by movement of said piston to close said opening,a restricted air outlet at said last named end of said piston wherebysaid piston and cylinder act as a dashpot when said relatively largeopening is closed.

OTTO SEIDENBERG.

